Shortcuts have randomly changed mid-project
The main thing to check is which keymap is active under the keymap settings in the preferences. Try the default ones to see which one fits the one you used previously.
For custom keymaps:
I favour disabling autosave under preferences so you can manually save the preferences &amp; keymaps. If you've customised the keymap, make sure to export it to a different folder as backup so you can always import it again later. Preferences are saved under &quot;Username&quot;/appdata\Roaming\Blender Foundation\Blender